Concrete composite water reducer

Abstract

The invention relates to a concrete composite water reducer, comprising a water reducer and a hydrophilic colloid. The concrete composite water reducer can improve the workability after using the water reducer, simultaneously an air entraining agent is added, a low-strength grade concrete with reasonable cost performance can be prepared by using a polycarboxylic acid water reducer, thus the problem of difficult popularization of the application of the polycarboxylic acid water reducer in the low-strength grade concrete.

Description

technical field [0001] The invention relates to a water-reducing agent, in particular to a water-reducing agent capable of improving concrete workability and other comprehensive properties and capable of preparing low-strength grade concrete. Background technique [0002] Concrete water reducer refers to an admixture that can reduce the amount of mixing water and improve the strength of concrete under the condition that the workability of concrete and the amount of cement remain unchanged; through surface activity, complexation, electrostatic repulsion or three-dimensional repulsion, etc. To hinder or destroy the flocculation structure of cement particles, so as to save the amount of cement while ensuring the workability and strength of concrete. [0003] Traditional water reducing agents can be divided into lignosulfonic acids, polycyclic aromatic salts and water-soluble resin sulfonic acids according to the composition materials. Water reducer, polycyclic aromatic hydroca...

AI Technical Summary

Problems solved by technology

However, the use of polycarboxylate superplasticizers has poor adaptability in medium and low-strength grade concrete. When directly used in medium and low-grade strength ready-mixed concrete, due to the high water-reducing rate of polycarboxylate superplasticizers, concrete water The amount of cement is reduced, but the total amount of concrete slurry is too small, which will seriously affect the working performance of concrete. Therefore, when using polycarboxylate superplasticizer directly, the proportion of concrete must be strictly controlled; however, for some cements, in medium and low strength concrete When using polycarboxylate water reducer directly in the medium, if the dosage is lowered to meet the requirements of low water reducing rate, the slump retention of concrete will not meet the requirements; at the same time, when preparing low-grade strength concrete, due to When preparing low-grade strength concrete, the quality of sand and gravel is poor, such as high mud content in sand and gravel, which increases the amount of polycarboxylate superplasticizer. Properly adjust mineral admixtures such as fly ash and sand rate Size, the cost of controlling the total amount of slurry per cubic concrete is much higher than that of using naphthalene-based, aliphatic and other water-reducing agents, and the cost performance is not suitable

Although polycarboxylate superplasticizers are used in combination with naphthalene-based superplasticizers to prepare low-grade strength concrete, when polycarboxylate superplasticizers come into contact with naphthalene-based superplasticizers, flocculation is likely to occur, and poly The performance of carboxylic acid superplasticizer is greatly damaged